Although from what I hear, the upgrades work with the voyager class figure as well, so it may still be worth your while to pick up the Voyager anyways.

I myself am happy with my Battle Begins Prime (the one with the best axe and the semi-decent Deluxe Megatron), although I will be picking up the Wingblade Prime as well since it's a bit more colorful than the battle-damaged Prime.

voyager is a nice figure, but the best in scale and nice is the deluxe one. it got the full mask and has the most show accurate axe. pretty much all complaints against it make no sense, it is a fun mold. so grab it or you could wait to get wingblade optimus prime,which is this mold (no battle damage) with the extra armor pieces, but has no axe apparantly (but it would be nice if included, seeing it is on the same mold sprue as the rest of his clear parts)

I think voyager is best, but the cybertronian deluxe is a close second. The cyber deluxe is very posable with tight joints, and looks cool as hell in a straight standing pose with his chest sticking out.

the earth mode deluxe's proportions are off. it's a cool figure, but between the two, the voyager is better.

although the ideal situation would be to get all three earth mode molds. earth mode deluxe for axe, voyager for being a better match to the show, and wingblade for the extra armor, to be put on the voyager.

Earth mode Deluxe all the way - it looks better and has better articulation than the Voyager, has the best axe and doesn't have the floppy shoulders that hurt the Voyager one either. Of course, Wingblade is coming out as well with the extra armour...